Canon imagePRESS C1 P, Service Manual, Page: 365 / 1265

Chapter 7
7-16
*1: Full potential control
*2: Implemented after potential control
*3: Fixing temperature at a certain level or less
*4: At single-color (Bk,L)
4 colors are 100 sheets
5 colors are 80 sheets
*5: At single-color (Bk,L)
4 colors are 500 sheets
5 colors are 400 sheets
*6: Simple potential control
7.4.5 Potential Control
0012-7463
imagePRESS C1 P / imagePRESS C1 / imagePRESS C1+ (Printer) / imagePRESS C1+
In order to realize stable printing, the machine executes the potential control against the electrostatic latent image factors, i.e. deterioration of the photosensitive
drum sensitivity and the environmental changes.
1. Startup Condition
The potential control has the following two control methods: the full potential control that measures Vg for each color, and the partial potential control that
calculates the potential of Magenta and reflects the result to other colors.
Full Potential Control
- At the warm-up rotation after first power on in the morning.
- When executing PASCAL control.
- At the last rotation after passing 500 sheets.
- When executing the service mode FUNCTION > DPC > DPC. (Drum surface potential measurement and dark area potential decay measurement)
Partial Potential Control
This control is performed at the following timing.
During continuous printing, when the counter reaches the following timing, print operation will be suspended and this control will be executed.
- Every 100 sheets (in case of 4-color full)
- Every 80 sheets (in case of 5-color full)
2. Drum Surface Potential Measurement
In the drum surface potential measurement, as a prearrangement of the measurement, it is checked if the charging assembly is worked normally by charging the
photosensitive drum with Vg in the environment and executing the potential measurement (Vd1) during the warm-up rotation or copying. If there is any fault,
an error message (E061-0001, 0007 to 0012) is displayed on the control panel. The Vd1 measurement is not available in the service mode (FUNCTION >DPC
>DPC).
In the normal drum surface potential measurement, set the grid bias (Vg1/Vg2) of the primary charging assembly, and measure the dark area potential (Vd) when
the laser is OFF and the light area potential (VL) when the laser is ON with the potential sensor.
Based on the measured Vd/VL and the grid bias (Vg), create a graph as indicated below.
F-7-16
3. Environment Control
In the environmental contrast potential control, the target contrast potential is determined by measuring the environment around the developing assembly.
The characteristic of the developer changes as the environment around the developing assembly changes, and it affects to the image density. Therefore, the target
contrast potential is determined by measuring the environment (temperature / humidity) around the developing assembly with the environment sensor.
Secondary transfer
ATCV control approx. 1 sec
Yes Yes Yes Yes Yes
Control item Required time
PASCAL
control
Initial rotation Interruption
Last rotation
after 500
sheets
JAM recovery
First in the
morning
Door open 400-sheet *4 2000-sheet *5
Vg1 Vg2
Vd2
Vd1
VL2
VL1
Vd
VL
Drum Surface Potential
Grid Bias
Vg1:-500V
Vg2:-800V
Environment Control